Rolladen-Schneider LS2

LS2
Role	Standard-class sailplane
National origin	Germany
Manufacturer	Rolladen-Schneider
First flight	ca. 1973
Number built	1

The Rolladen-Schneider LS2 is a 15-metre span single seat glider prototype with trailing edge air brakes, designed and built by Rolladen-Schneider Flugzeugbau GmbH c. 1973.

The LS2 was designed by Wolf Lemke and Walter Schneider in response to changes in the Standard Class rules. A single experimental prototype was built. First flown in 1973, it won the German Championships that year and went on to win the World championships in Australia in 1974.

The design was nevertheless unsatisfactory. The air brakes occupied most of the trailing edge of the wing, being intended also as a means to lower speeds and improve climb rates in thermals. Class rules did not allow these surfaces to be coupled to the ailerons. The resultant sluggish roll rate from the very short ailerons led to poor and unsafe flying characteristics. Thrice World Champion Helmut Reichmann reportedly said the performance advantages were not worth the extra pilot workload.

The LS2 highlighted inconsistencies in the rules that promoted unwise design trends, with trade-offs having to be made by designers between competitiveness and safety. Many observers also felt that trailing edge air brakes were against the spirit of the Standard Class, an issue that affected other types such as the PIK-20, Libelle and Schreder HP-8.

The International Gliding Commission voted a new set of rules in 1974, prohibiting any lift-enhancing devices in the Standard Class and creating the 15 metre Class where these were allowed without any restriction.

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